I am pleased to announce the publication of the following two papers focusing on bioenergetics and reproductive biology of minke whales in Iceland. Paper 1: Christiansen, F., Vikingsson, G.A., Rasmussen, M. & Lusseau, D. 2013. Minke whales maximise energy storage on their feeding grounds. Journal of Experimental Biology 216: 427-436. Abstract: Seasonal trends in energy storage of the minke whale (Balaenoptera acutorostrata), a capital breeder, were investigated in Iceland, a North Atlantic feeding ground. The aim was to better understand the energy acquisition strategies of minke whales and the energetic costs that different reproductive classes face during the breeding season. We modelled total blubber volume, using blubber thickness and morphometric measurements of individual whales. Blubber volume was influenced by body length, and was higher for pregnant females than mature whales. Blubber volume increased linearly through the feeding season at the same rate for mature (mean ± s.e.m.=0.0028±0.00103 m3 day-1; N=61 male, 5 female) and pregnant whales (0.0024±0.00100 m3 day-1; N=49), suggesting that minke whales aim to maximise energy storage while on the feeding grounds. The total amount of blubber accumulated over the feeding season (0.51±0.119 m3 for mature and 0.43±0.112 m3 for pregnant whales), together with energy stored as muscle and intra-abdominal fats, constitutes the total amount of energy available for reproduction (fetus development and lactation) on the breeding grounds, as well as migration, daily field metabolic rates, growth and body maintenance. No seasonal variation was observed for immature whales (N=4 male, 12 female), suggesting that they are investing most of their excess energy into growth rather than reproduction, in order to reach the length of sexual maturity faster and start reproducing earlier. Our novel modelling approach provides insight into large whale bioenergetics and life history strategies, as well as the relationship between single-site measurement of blubber thickness and total blubber volume. Paper 2: Christiansen, F., Vikingsson, G.A., Rasmussen, M. & Lusseau, D. 2013. Female body condition affects foetal growth in a capital breeding mysticete. Functional Ecology. doi:10.1111/1365-2435.12200 Abstract: 1. Understanding how female body condition (FBC) influences foetal development, and hence offspring production, is fundamental for our understanding of species reproductive physiology and life history. 2. We investigated the effects of FBC on foetus growth in common minke whales. Pregnant minke whales were sampled around Iceland during the summer feeding seasons between 2003 and 2007 and the length and weight of their foetuses were measured. FBC was modelled as the relative difference between measured blubber volume and the average expected blubber volume of individual whales. Generalized linear models were used to test the effect of FBC on foetus length, while accounting for the daily growth in foetus size through gestation, as well as other covariates. 3. Foetus length increased curvilinearly through the study period at an average rate of 0.964 cm day-1 (SE = 0.138). The effect of FBC on foetal length was nonlinear, showing an almost linear positive relationship for females in poorer body condition (FBC < 0), which levelled off at better body conditions (FBC > 0). 4. The curvilinear relationship between FBC and foetus growth was confirmed by fitting a generalized additive model and by running separate analyses on two subsets of data separating females in poorer and better condition. 5. Our findings suggest that females that are in poorer body condition reduce their energetic investment in their foetus proportionately to their condition, most likely to help maintain a high survival probability. That foetus length did not increase for females in better body condition suggests that females have an upper limit on the amount of energy they will or can invest in their foetus. Reducing the size at birth by reducing the gestation period is also unlikely, because the reproductive cycle of balaenopterids is strongly linked to their seasonal migration between feeding grounds and breeding grounds. This study is the first to demonstrate that FBC can affect foetus growth in a capital breeding mysticete. Please contact me by email for a copy of these articles if you are interested: f.christiansen@live.se. I will also be attending the SMM conference next week in New Zealand, and present some of these results on Wednesday Dec 11 at 09:00 in Castle 2. Best regards, Fredrik Christiansen Research fellow Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Warrnambool Campus, PO Box 423, Warrnambool, VIC 3280 Phone: +61 3 55633080 Email: f.christiansen@deakin.edu.au, f.christiansen@live.se Publications: http://scholar.google.com.au/citations?user=vkA5Y3EAAAAJ&hl=en&oi=sra